A study of house resting population of Culex pipiens fatigans by the method of hand collection in the filariasis vector control programme in Ceylon

The diversity and biting activity of Mansonia is important to be determined as to predict the incriminated vector and pattern the mosquito behaviour in establishing the vector control programme. The present study has been successfully conducted to investigate the prolonged biting behaviour of Mansonia spp. in two villages in Banyuasin Regency, South Sumatera Province-Indonesia, using Human Landing Collection method (HLC) in indoor and outdoor for 14 months. The result shows that there are 4956 Mansonia spp. mosquitoes collected during the study comprising 6 species: Mansonia uniformis (40.37%), Mansonia annulifera (32.04%), Mansonia indiana (19.97%), Mansonia bonneae (5.28), Mansonia dives (2.14%); and Mansonia annulata (0.18%). The further investigation confirms that Mansonia uniformis (41.254%) and Mansonia bonneae (45.490%) become the most dominant species caught in Sedang village and Muara Sugih village, respectively and find higher biting activities in outdoor than indoor with biting peaked time at approximately 18.00-19.00. However, the biting activities is also observed in daytime, indicating the behaviour change of Mansonia spp. as the nocturnal mosquitoes. Furthermore, the periods of the highest biting rates are found in April 2017 and May 2017 in Sedang village and May 2018 in Muara Sugih Village. The high period of biting activities and behaviours become the valuable information to arrange the further controlling action of filariasis transmission in Sedang and Muara Sugih Villages as the endemic area of filariasis in South Sumatera, Indonesia.

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Past exposure and the dynamics of lymphatic filariasis infection in young children

Epidemiology and Infection ◽

10.1017/s095026880000131x ◽

1996 ◽

Vol 117 (1) ◽

pp. 195-201 ◽

Cited By ~ 5

Author(s):

A. Srividya ◽

P. K. Das ◽

S. Subramanian ◽

K. D. Ramaiah ◽

B. T. Grenfell ◽

...

Keyword(s):

Young Children ◽

Vector Control ◽

Wuchereria Bancrofti ◽

Control Programme ◽

Infection Prevalence ◽

Past Exposure ◽

Vector Control Programme ◽

Model Predictions ◽

Current Infection ◽

Dynamical Function

SummaryThis study utilizes parallel, longitudinal entomological and parasitological data collected during a 5-year vector control programme in Pondicherry, South India, to quantify Wuchereria bancrofti transmission from the vector to the human population. A simple mathematical model, derived from the standard catalytic model, is used to examine the hypothesis that current infection prevalence in young children is a dynamical function of their cumulative past exposure to infective bites. Maximum likelihood fits of the model to the observed data indicate a constant child infection rate with age, above a threshold representing the pre-patent period, or equivalently, the cumulative biting intensity required to produce patent infections. Extrapolation of the model allows the crude estimation of the equilibrium microfilaria age-prevalence curve due to control. The results suggest that vector control alone may have little impact on the overall age-prevalence of infection even when sustained for long periods. These observations are discussed in terms of the likely impact of density dependent mechanisms, such as acquired immunity, on model predictions.

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Small-scale field assessment of efficacy of the autodissemination approach against Aedes sp. in an urban area

10.1101/2020.01.13.904094 ◽

2020 ◽

Author(s):

Ahmad Mohiddin Mohd Ngesom ◽

Hidayatulfathi Othman ◽

Rawaida Bahauddin ◽

Nazni Wasi Ahmad ◽

Lee Han Lim ◽

...

Keyword(s):

Vector Control ◽

Large Scale ◽

Field Trials ◽

Control Programme ◽

Small Scale ◽

Vector Control Programme ◽

Breeding Habitats ◽

Scale Field ◽

Large Scale Field ◽

Future Evaluation

AbstractThis is the first study to evaluate the efficacy of an autodissemination approach, as suggested by WHO. Therefore, the efficacy of an autodissemination approach in small-scale field trials against wild Aedes sp. population was evaluated in an urbanized setting, Malaysia. Lethal ovitraps enhanced with pyriproxyfen were used to control Aedes sp. populations at treatment sites, with the autodissemination activity was assessed using the WHO larval bioassays. Lethal ovitraps enhanced with pyriproxyfen effectively reduced of Aedes sp. population. All autodissemination stations were shown to be visited by Aedes sp. mosquitoes with 100% complete inhibition against eggs and larvae development. In the larvae bioassay, pupae mortality ranged from 14 to 40%. Statistically, a significant reduction of Aedes sp. population in the treatment sites compared to the untreated areas. The study proved for the autodissemination of pyriproxyfen to breeding habitats by wild Aedes sp. This technique is highly potentially for vector control activities. Future evaluation should focus on large-scale field trials.Author SummarySince 2012, Dataran Automobil, Seksyen 15, Shah Alam, was declared as one of the dengue hotspot areas. Major vector control activities were conducted by government, NGOs, social communities, and local authorities, but the number still rising. We conducted a new invention of autodissemination concepts in this area by an entomological study on mosquito populations reduction and dispersal abilities of the technique. We found that the technique has proven to control mosquito populations, but the other factors such as epidemiology link still unclear and need further clarification. Our finding highlighted the effectiveness of autodissemination strategies that can be considered as one of the alternative tools in vector control programme.

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Status of Insecticide Resistance of Malaria Vector Anopheles stephensi towards Insecticides in Alwar District of Rajasthan, India

JOURNAL OF COMMUNICABLE DISEASES ◽

10.24321/0019.5138.202109 ◽

2021 ◽

Vol 53 (01) ◽

pp. 58-61

Author(s):

Sarmad Moin ◽

Keyword(s):

Insecticide Resistance ◽

Vector Control ◽

Malaria Vector ◽

Anopheles Stephensi ◽

Control Programme ◽

Vector Control Programme ◽

Intermediate Resistance ◽

Susceptibility Study ◽

Standardized Method

Pyrethroids have been developed as a powerful insecticide that is widely used for space spray and residual indoor spraying, with impregnated nets included in the vector control programme. Insecticide resistance reduces the effectiveness of pesticides. Therefore, the vector susceptibility condition of the Anopheles stephensi is monitored in order to select the active ones. The current study is being conducted in a malaria-ridden area in various parts of the Alwar region of Rajasthan, India, against the malaria vector An. stephensi. The Susceptibility study was conducted by the WHO standardized method using the diagnostic doses of DDT, Alpha-cypermethrin and Deltamethrin. An. stephensi showed intermediate resistance to DDT from all over the study while susceptible to Alpha-cypermethrin and Deltamethrin.

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Evaluation of the « Time/Risk » Probability of being Infected and its Evolution Before/After a Long Term Village Scale Malaria Vector Control Programme in Angola

Asian Journal of Research in Infectious Diseases ◽

10.9734/ajrid/2021/v7i330219 ◽

2021 ◽

pp. 36-48

Author(s):

P. Carnevale ◽

N. Carnevale ◽

G. Carnevale

Keyword(s):

Vector Control ◽

Classical Method ◽

Control Programme ◽

Control Measures ◽

Malaria Vector Control ◽

Reproduction Rate ◽

Insecticide Treated Nets ◽

Vector Control Programme ◽

One Year

Three main entomological indicators are classically used in the epidemiology of malaria: the inoculation rate (“h”) of Ross, the vectorial capacity (“C”) of Garrett-Jones and the reproduction rate (“z”) of Macdonald. In spite of their undoubtfully usefulness it appeared that their formulae did not integrate the key parameter of “t” i.e. the time of exposure and therefore the probabilities of being infected according to the entomological condition (density, infectivity, longevity of the vectors) but also the time/risk and the reduction of this risk when some village-scale vector control measures are implemented. To deal with this approach we used the Briley’s formula, elaborated some years ago, to analyze the time/risk of being infected in the framework of a long term village scale vector control programme implemented around Balombo (Benguela Province, Angola) with classical method (inside residual spraying) and newly developed tool s (insecticide treated plastic sheeting) used alone or in association with the classical long lasting insecticide treated nets. Before vector control the risk was almost 20% in one week, 60% in one month and 100% in 3 months and this explain why plasmodic index are so high in this area without any organized vector control programme. The 3 methods actually reduced the risks which become of the order of 2% in one week, 10% in one month, 26% in one trimester but 70% in one year; the three methods had the same efficacy in reducing these risks. The fact that the risk reach 70% in one year even with right vector control shows the needs of renewing regularly the operations, the needs of other than entomological methods of prevention but also that immunity could be maintained and feared “rebound” was not observed even during the long term of the programme.

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Use of Bacillus thuringiensis var israelensis as a viable option in an Integrated Malaria Vector Control Programme in the Kumasi Metropolis, Ghana

Parasites & Vectors ◽

10.1186/1756-3305-6-116 ◽

2013 ◽

Vol 6 (1) ◽

pp. 116 ◽

Cited By ~ 26

Author(s):

Rita Nartey ◽

Ellis Owusu-Dabo ◽

Thomas Kruppa ◽

Sandra Baffour-Awuah ◽

Augustina Annan ◽

...

Keyword(s):

Bacillus Thuringiensis ◽

Vector Control ◽

Malaria Vector ◽

Control Programme ◽

Malaria Vector Control ◽

Viable Option ◽

Vector Control Programme

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“House Plasmodial Prevalence Index” Another Relevant Indicator of Evaluating a Malaria Vector Control Operations, Example of Capango Village (Benguela Province, Angola)

International Journal of TROPICAL DISEASE & Health ◽

10.9734/ijtdh/2020/v41i730296 ◽

2020 ◽

pp. 45-53

Author(s):

P. Carnevale ◽

J. C. Toto ◽

V. Foumane

Keyword(s):

Vector Control ◽

Control Programme ◽

Malaria Vector Control ◽

Prevalence Index ◽

Cross Sectional ◽

Longitudinal Surveys ◽

Vector Control Programme ◽

Control Programmes ◽

The Impact ◽

Positive Index

The WHO fascicule “Information systems for the evaluation of malaria control programmes” identified as outcome target “the proportion of households targeted for use of nets using at least one impregnated bednet” [1]. The parasitological evaluation of the efficacy of vector control programme is mainly based on the plasmodial prevalence rate evaluated by cross sectional or longitudinal surveys on representative sample of the human population targeted. For the new “House plasmodial” index we decided to combine the 2 indicators: the classical human plasmodial prevalence and house considering as positive any house with “at least one symptomless inhabitant having at least one positive thick film during the survey”. We used this new indicator when analyzing data gained during 24 regularly done parasitological surveys during 5 years in Capango village where a vector control (VC) programme was implemented using both Long Lasting Nets PermaNet© 2.0 and deltamethrin treated wall lining called ZeroFly© inside every house. Surveys were done during 2 years before VC and 3 years after. It appeared that the House Plasmodial positive index showed the same trends and level as the classical human plasmodial prevalence and clearly indicated the impact of vector control in reducing the overall plasmodial prevalence in the targeted village. On the other hand it appeared repeating surveys identified “frequently positive houses” (=found positive in some 50% of surveys) and therefore to be prioritized for control and those “scarcely positive” (20% of surveys). The House Plasmodial Prevalence index appeared relevant and reliable, interesting to be used in vector control programme while easy to get and should be considered in other epidemiological situation.

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Onchocerciasis control in Ghana (1974–2016)

Parasites & Vectors ◽

10.1186/s13071-020-04507-2 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Nana-Kwadwo Biritwum ◽

Dziedzom K. de Souza ◽

Odame Asiedu ◽

Benjamin Marfo ◽

Uche Veronica Amazigo ◽

...

Keyword(s):

Confidence Interval ◽

Vector Control ◽

Control Strategy ◽

Financial Support ◽

Control Programme ◽

Ivermectin Treatment ◽

Mobile Community ◽

The Mean ◽

The Impact ◽

Onchocerciasis Control

Abstract Background The control of onchocerciasis in Ghana started in 1974 under the auspices of the Onchocerciasis Control Programme (OCP). Between 1974 and 2002, a combination of approaches including vector control, mobile community ivermectin treatment, and community-directed treatment with ivermectin (CDTI) were employed. From 1997, CDTI became the main control strategy employed by the Ghana OCP (GOCP). This review was undertaken to assess the impact of the control interventions on onchocerciasis in Ghana between 1974 and 2016, since which time the focus has changed from control to elimination. Methods In this paper, we review programme data from 1974 to 2016 to assess the impact of control activities on prevalence indicators of onchocerciasis. This review includes an evaluation of CDTI implementation, microfilaria (Mf) prevalence assessments and rapid epidemiological mapping of onchocerciasis results. Results This review indicates that the control of onchocerciasis in Ghana has been very successful, with a significant decrease in the prevalence of infection from 69.13% [95% confidence interval) CI 60.24–78.01] in 1975 to 0.72% (95% CI 0.19–1.26) in 2015. Similarly, the mean community Mf load decreased from 14.48 MF/skin snip in 1975 to 0.07 MF/skin snip (95% CI 0.00–0.19) in 2015. Between 1997 and 2016, the therapeutic coverage increased from 58.50 to 83.80%, with nearly 100 million ivermectin tablets distributed. Conclusions Despite the significant reduction in the prevalence of onchocerciasis in Ghana, there are still communities with MF prevalence above 1%. As the focus of the GOCP has changed from the control of onchocerciasis to its elimination, both guidance and financial support are required to ensure that the latter goal is met.

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